function replaceImage(){
	var arr		= document.getElementsByTagName('img');
	for(var i=0,l = arr.length;i<l;i++){
		var	e	= arr[i];
		if(e.attributes['usrc']!=undefined){
			var tmp 	= e.attributes['usrc'].nodeValue;
			var src 	= "";
			var strs	= tmp.split("_");
			for (ii=0;ii<strs.length ;ii++ )
			{
				if(ii==0){
					src = src + base64decode(strs[ii]);
				}else{
					src = src + "_" + strs[ii];
				}
			} 
			e.src = src;
		}
	}
}

function base64encode(str) { 
str = utf16to8(str); 
var out, i, len;    
var c1, c2, c3;    
var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 
len = str.length;    
i = 0;    
out = "";    
while(i < len) { 
c1 = str.charCodeAt(i++) & 0xff;    
if(i == len){ 
out += base64EncodeChars.charAt(c1 >> 2); 
out += base64EncodeChars.charAt((c1 & 0x3) << 4); 
out += "==";       
break;    
}    
c2 = str.charCodeAt(i++);    
if(i == len)    {        
out += base64EncodeChars.charAt(c1 >> 2);        
out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));        
out += base64EncodeChars.charAt((c2 & 0xF) << 2);        
out += "=";        
break;    
} 
c3 = str.charCodeAt(i++);    
out += base64EncodeChars.charAt(c1 >> 2);    
out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));    
out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6));    
out += base64EncodeChars.charAt(c3 & 0x3F);    
}   
return out; 
} 
function base64decode(str){ 
var c1, c2, c3, c4;    
var i, len, out;   
var base64DecodeChars = new Array(-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, 
-1,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, 
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1); 
len = str.length;    
i = 0;    
out = "";    
while(i < len) {    
do {        
c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff];    
} 
while(i < len && c1 == -1);    
if(c1 == -1) break;   
do {        
c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff];    
} 
while(i < len && c2 == -1);    
if(c2 == -1)  break;    
out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4));    
do {        
c3 = str.charCodeAt(i++) & 0xff;        
if(c3 == 61) return out;        
c3 = base64DecodeChars[c3];    
} 
while(i < len && c3 == -1);    
if(c3 == -1) break;    
out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2));    
do {        
c4 = str.charCodeAt(i++) & 0xff;        
if(c4 == 61) return out;        
c4 = base64DecodeChars[c4];    
} 
while(i < len && c4 == -1);    
if(c4 == -1) break;    
out += String.fromCharCode(((c3 & 0x03) << 6) | c4);    
} 
out = utf8to16(out); 
return out; 
} 
function utf16to8(str) {    
var out, i, len, c;    
out = "";    len = str.length;    
for(i = 0; i < len; i++) {    
c = str.charCodeAt(i);    
if ((c >= 0x0001) && (c <= 0x007F)) {        
out += str.charAt(i);    
} else if (c > 0x07FF) {        
out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));        
out += String.fromCharCode(0x80 | ((c >>  6) & 0x3F));        
out += String.fromCharCode(0x80 | ((c >>  0) & 0x3F));    
} else {        
out += String.fromCharCode(0xC0 | ((c >>  6) & 0x1F));        
out += String.fromCharCode(0x80 | ((c >>  0) & 0x3F));    
}    
}    
return out; 
} 

function utf8to16(str) {    
var out, i, len, c;    
var char2, char3;    
out = "";    
len = str.length;    
i = 0;    
while(i < len) {    
c = str.charCodeAt(i++);    
switch(c >> 4){       
case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:            
out += str.charAt(i-1);        
break;      
case 12: case 13:              
char2 = str.charCodeAt(i++);        
out += String.fromCharCode(((c & 0x1F) << 6)|(char2 & 0x3F));        
break;      
case 14:               
char2 = str.charCodeAt(i++);        
char3 = str.charCodeAt(i++);        
out += String.fromCharCode(((c & 0x0F) << 12)|((char2 & 0x3F) << 6)|((char3 & 0x3F) << 0)); 
break;    
} 
}   
return out; 
}